What is the ampacity of your 16 AWG wire? Is it in free air or in a big bundle? Does it have 105C insulation, 90C, or 75C? There are many factors that will determine how much current can go through those wires without causing a problem. Go small enough, and your wires are now a fusible link. If they melt, and are contained in a metal box, that still may not be a problem.
Many areas are now requiring just about anything that plugs in to be UL or NRTL listed/certified. We've got that to deal with here in WA. The only trouble is enforcing it. I can buy a Chinese blender that isn't listed and plug it into my kitchen. That would be a violation of the WAC, but there's no inspector here to catch it. They try to stop it at the seller, but they can't with online sales. I still see stuff at Home Depot that isn't listed (e.g. generators). We also get stopped when pulling a permit to do something (e.g. move an old hard wired drill or mill to another building). Being hard wired on its own circuit, we need to pull a permit. The inspector will check that old device for a UL or NRTL label and fail the install if it isn't listed/certified.